<span>The maximum possible efficiency, i.e the efficiency of a Carnot engine , is give by the ratio of the absolute temperatures of hot and cold reservoir.
η_max = 1 - (T_c/T_h)
For this engine:
η_max = 1 - [ (20 +273)K/(600 + 273)K ] = 0.66 = 66%
The actual efficiency of the engine is 30%, i.e.
η = 0.3 ∙ 0.664 = 0.20 = 20 %
On the other hand thermal efficiency is defined as the ratio of work done to the amount of heat absorbed from hot reservoir:
η = W/Q_h
So the heat required from hot reservoir is:
Q_h = W/η = 1000J / 0.20 = 5000J</span>
The force that acts on all objects, all the time on Earth is gravitational force.
The force that surface exert on an object perpendicularly is normal reaction.
<h3>What force acts on all objects, all the time on Earth?</h3>
- Force due to gravity is gravitational pull on objects due to its position on earth's surface.
The force due to gravity on object's is calculated by applying Newton's second law of motion as follows;
F = mg
where;
- m is the mass of the object
- g is acceleration due to gravity
The force that surface exert on an object perpendicularly is normal reaction.
Thus, the force that acts on all objects, all the time on Earth is gravitational force.
Learn more about force of gravity here: brainly.com/question/2537310
Answer:
1 second later the vehicle's velocity will be:

5 seconds later the vehicle's velocity will be:

Explanation:
Recall the formula for the velocity of an object under constant accelerated motion (with acceleration "
"):

Therefore, in this case
and 
so we can estimate the velocity of the vehicle at different times just by replacing the requested "t" in the expression:

Conductors allow<span> for </span>charge<span> transfer </span>through<span> the free movement of </span><span>electrons
</span>